Geographic Tongue: The Mysterious Condition That Makes Maps In Your Mouth | IFLScience
Geographic tongue (GT) is a medical condition in which the upper layer of the tongue, which consists of tiny hair-like protrusions (called papillae), is damaged due to an expanding inflammation. As a result, red patches devoid of papillae can be observed on the surface of the tongue. A noticeable characteristic of the condition is an evolving map-like appearance of the affected tongue (hence its name).